1. Field of the Invention
The present invention relates to antidepressants, and particularly to antidepressant compounds that are dichlorinated compounds of the dihydroethanoanthracene family.
2. Description of the Related Art
Depression is a mood disorder that causes a persistent feeling of sadness. The pharmacotherapy of depression started in the 1950s. There are currently ten to twenty different drugs marketed as antidepressants, depending on the country. Known antidepressants include selective serotonin reuptake inhibitors (SSRIs), atypical antidepressants, tricyclic antidepressants (TCAs), and monoamine oxidase inhibitors (MAOIs). Unfortunately, side effects are common in all antidepressants. Side effects of antidepressants are the main reason that many people stop a course of depression medication. Antidepressant and anxiolytic drugs without side effects are still being sought.
All of the selective serotonin reuptake inhibitor (SSRI) antidepressants, such as citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine and sertraline (brand names Zoloft® [Zoloft is a registered trademark of Pfizer Inc. of New York, N.Y.]) possess halogen atoms at specific positions, which are key determinants for the drugs' specificity for serotonin transporter (SERT). It is believed that halogen atoms can also increase lipophilicity, binding affinity, and membrane permeability to fill hydrophobic cavities in the protein binding site, to facilitate the blood-brain barrier crossing, and to prolong the lifetime of the drug, thereby improving bioavailability. However, the effects of introducing halogen atoms to a particular compound have been poorly studied. As such, many anxiolytic and antidepressant compounds do not include halogen atoms.
The tetracyclic drugs benzoctamine(9,10-dihydro-N-methyl-9,10-ethanoanthracene-9-methanamine) and maprotiline (9,10-dihydro-N-methyl-9,10-ethanoanthracene-9-propanamine) are bridged anthracene compounds that do not possess halogen atoms. Despite their structural similarity, benzoctamine is primarily an anxiolytic drug that exhibits antagonistic effects on norepinephrine, while maprotiline is an antidepressant and anxiolytic drug that is useful as a norepinephrine reuptake inhibitor. Seizures, leukopenia and skin reactions are common side effects of maprotiline.
Thus, antidepressants compounds solving the aforementioned problems are desired.